Temperature-controlled alarm



W. E. FOX

TEMPI IRATURE CONTROLLED ALARM Sept. 13, 1927. 1,642,649

Filed May 5, 1926 WITNESS:

r36 an 1M I 0x INVENTOR ATTORNEY Patented Sept. 13, 1927.

UNITED STATES WALTER E. FOX, OF OMAK, WASHINGTON.

TEMPERATURE-CONTROLLED ALARM.

Application filed Hut, 1926. Serial No. 106,502.

The object of this invention is to provide an alarm especially adapted for use 1n orchards, or orange groves, and comprising electric contact making mechanism for connection with'a circuit leading to a dwelling house, or to some other suitable point, so that in the event the outside temperature reaches a point near freezing, an alarm will be given at any hour of the night, in, order that smudges, or heating means, may be employed with a view to saving a crop from injury by frost.

.A further object is to provide a durable and efficient device which may be manufactured at a low cost.

A further object is to provide a particular form of contact making device, including an element adapted to expand and contract,

and includin regulating means.

With the oregoing and other objects in view, the invention consists in the novel construction and arrangement of elements described, illustrated and claimed, it being understood that modifications may be made .within the scope of the claims, without departing from the spirit of the invention.

In the drawings forming part ofthis application,

Figure 1 may be regarded as a plan vlew, with a diagrammatic showing of the alarm circuit.

Figure 2 is a view chiefly in longitudinal section thru the mounting means for the contact elements, that portion of the structure at the right of Figure 1 being broken awa Figure 3 is a detail view in section and elevation, showing the elements at the right of Figure 1.

Figure 4 is a perspective view of a contact arm carrying a special form of connection for engagement by the wire or other element adapted to expand and contract under temperature changes.

Figure 5 is a section on line 5-5 of Figure 2.

The mounting means may include an elongated element or strip 10 having one end recemed as shown at 11, and this recessed portion being closed by a plate or block 12. The elements 10 and 12 may be of wood, or of other suitable material, and if one or more of the mntact elements are mounte directl on the elements referred to, the latter will be relied upon for insuleting purposes.

The element intended to expand and contract with the variations in temperature, is designated 15, and a braided or twisted copper wire-is suitable for this purpose the required length being provided, for which reason element 10 has the form of a strip, the length to be, say six feet. Guiding devices for the wire 15 are shown at various points, and are designated 16, and one end of wire 15 has an eye member 17 formed thereon for engagement by eye member 18 formed on the threaded stem 19 engaged by a milled adjusting nut 20 at the outer end of sleeve 21.

A wire 23 is connected with wire 15, by soldering at 24, this wire 23 being connected with a binding post or the like 25, and the latter having connected therewith a. wire 26 leading to one terminal of bell or other alarm desi nated 27. The op site terminal is connected by wire 28 with ttery 29, and one battery terminal is connected with wire 30 which, leads to binding post 31.

The binding ost 31is in electrical communication wit contact strip 32 carrying a contact point 33 for cooperating with the flattened end 34; of a contact arm 35 mounted in recess 11. A. connecting or mountin element 36 extends thru cover plate 12 and thru the strip 32, and serves an obvious purpose. i

The contact arm 35 is pivotally mounted at 38, and a tension spring 39 is connected with the arm, at the point shown, and is connected with the'inner wall of recess 11' at the point 39'. Arm 35 is forked, and the prongs 40 and 41 are connected by bridge member 42' having an aperture 43 therein, and the book 44 formed on the end of wire v15, engages the aperture 43, so that u on the contraction of wire 15, the left han end ofarm 35, in Figures 2 and 4 will move u wardly,

into position for making electrica contact with element 33.

It is the intention that contact shall be made as indicated, when the temperature falls to a point near freezing, but before the danger point has actually been reached so that: the owner or individual in charge 0 the orchard may have sufficient warning to permit him to take steps for avoiding injury to the crop by frost, or b freezing. In setting the device in order t at it may function properly, a standard thermometer is employed, and assuming that the outside temperature is at the danger point, a j l i.

is made so that the contacts will come together, and the alarm will be sounded, and will continue to sound, in actual operation, until the circuit is broken, after the warn: ing has served its purpose. It will be understood that the efl'ective length of Wire 15 is determined by nut 20 in making the original adjustment, or at any subsequent time when the device is being tested and placed in position for use. I

It will be observed that contact strip 32 is deflected awayirom the under side of cover plate 12, and provides flexibility after contact has been effected.

Having thus described the invention, what is claimed is:

In a device of the class described, a stationary contact element, mounting means therefor, said element having its free end deflected away from the mounting means, a pivoted contact arm cooperating with the stationary contact element, the arm including a forked portion, and a bridge member connecting the elements of the fork, said bridging member being apertured, a temperature controlled element comprising a wire having a deflected end portion connected with the bridging element of the pivoted arm, means for mounting said wire, and permitting movement of the latter longitudinally, incident to expansion and contraction, one end of the wire being formed with an eye portion, and adjusting means connected with the eye portion, said means including relatively movable threaded devices.

WALTER E. FOX. 

